AquAdvantage salmon

AquAdvantage salmon is a genetically engineered (GE) salmon produced by AquaBounty Technologies. AquAdvantage salmon grow to market size in 16 to 18 months instead of the usual 30 required for Atlantic salmon.[1] In early September 2010, the FDA announced findings that the GE salmon is safe to eat. If approved, the fish will be the first genetically engineered animal commercially sold as food in the United States.[2] AquAdvantage salmon are identified as "Triploid hemizygous, all-female Atlantic salmon (Salmo salar) bearing a single copy of the α-form of the opAFP-GHc2 rDNA construct at the α-locus in the EO-1α lineage."[3] In other words, the salmon will each have three complete sets of chromosomes instead of two, and all of the fish will be females. In December 2012, the U.S. Food and Drug Administration took preliminary steps to allow commercialization of the AquAdvantage salmon.[4]

Regulation and Approval Process

The U.S. government regulates the recombinant (genetically engineered) DNA in the salmon as a New Animal Drug (NAD). Thus, it falls under the regulatory authority of the FDA. For more information, see the article on the AquAdvantage Salmon FDA Approval Process.

Environmental Assessment

Prior to FDA approval, the AquAdvantage was required to undergo an Environmental Assessment (EA). One of the main concerns addressed in the assessment is the potential for the GE salmon to escape into the wild, particularly if it would be able to survive there and compete with wild populations and/or interbreed with wild populations.[5] For more information, see the article on the AquAdvantage Salmon Environmental Assessment.

Creation of All-Female Triploid Population

The process of creating an all-female triploid population of GE salmon begins with female GE salmon and irradiated sperm of Arctic char, another fish species.[6] The process used to create an all-female population is known as gynogenesis, which is described as follows: "Briefly, irradiated sperm are introduced to eggs, followed by a pressure treatment to result in diploid “twin” offspring. In this case, ABT uses Arctic char milt that has been irradiated so that no Arctic char DNA is present in the gynogen population. In the event that the milt irradiation was not successful, the offspring would be an Arctic char / Atlantic salmon hybrid. These fish are readily identifiable by their differential markings and phenotypic appearance. As such, these hybrid fish can be easily removed without extensive testing."

The remaining all-female population are subjected to "masculinization" using 17-methyltestosterone. The females become "neomales" (genetically female fish that produce milt (sperm) instead of viable eggs). Upon sexual maturity, the neomales are bred with non-GE Atlantic salmon females. Then, fertilized eggs are "subjected to pressure shock treatment," turning them into triploids with two sets of chromosomes from the non-GE female salmon and one set of chromosomes from the neomale GE salmon. These fish, the female triploids, will be commercialized as AquAdvantage salmon. Triploid salmon are incapable of reproduction.

Safety Testing of AquAdvantage Salmon

The FDA released its assessment of AquaBounty's safety testing of AquAdvantage salmon in a 180 page document in September 2010.[7] The science used to justify the GE salmon's safety was called "sloppy" and "misleading" by critics (and even noted as such by the FDA in several cases in its assessment).[8] For more information, see the article on Concerns About Science Justifying the Safety of AquAdvantage Salmon.